General

The Actueel Hoogtebestand Nederland versie 2 (AHN2), was made available 2014-03-06. The dataset covers the topography of the Netherlands (nl), measured from 2011 through 2012.

three star open Web data

Formats

The data is available in pointclouds (las) and as a map (tiff).

Services

Using the AHN2 as a background map can be done using one of the OGV web services:

The full list is available at https://www.pdok.nl/nl/producten/pdok-services/overzicht-urls. The relevant url's are:
WMS:

WFS:

WMTS:

WCS

If you're using QGIS you can use the PDOK plugin which is very handy (in dutch).

Downloading

To download the data use one of the atomfeeds to get a list of files.

https://www.pdok.nl/nl/producten/pdok-downloads/atomfeeds

Examples

Qgis

Load the PDOK plugin. Add the AHN2 WMTS service from the list (for viewing). You should see something like:

Python

The OWSlib package is demonstrated in this Python Notebook: https://svn.oss.deltares.nl/repos/openearthtools/trunk/python/notebooks/ahn2.ipynb accessible after free registration for OpenEarth.

Web browser

For using WMS or WCS in a we browser see our WMS primer or WCS primer:

http://geodata.nationaalgeoregister.nl/ahn2/wms?service=WMS&request=GetMap&layers=ahn2_5m&width=800&height=600&bbox=94000,466000,96000,468000&crs=epsg:28992&format=image/png

Matlab

OpenEarthTools has Matlab OGC functions wcs and wms for using the AHN(2) web services, which can be dowloaded here accessible after free registration for OpenEarth. We use WCS here so we can use our own colormap to highlight details (West of Netherlands is roughly between -5 for polders and +25 for dunes) rather then WMS which has a fixed colormap (needed to accommodate the full DEM range incl. Vaalserberg at +322m)

server = 'http://geodata.nationaalgeoregister.nl/ahn2/wms?';
[url,OPT,lim] = wcs('server',server,...
    'coverage','ahn2:ahn2_5m',...
    'format','GeoTiff',... % only format offered
    'crs','epsg:28992',... % RD
    'axis',[94000 466000 96000 468000],... % around Kaag
    'resx',5,'resy',5); % 5m, native resolution

urlwrite(url,['tmp',OPT.format]);

im = imread(['tmp',OPT.format]);
im(im<-3.402e+38)=NaN;  % ahn2
%im(im==-32768   )=NaN;  % ahn1
pcolorcorcen(OPT.x,OPT.y,double(im))
tickmap('xy')


Note the elevated railway track, the higher elevations of the old dunes of Warmond, the lower elevations in the peat/polders in Leiden North, the deblanked waterways, the townhouse blocks with the deblanked ditches, but also the unfiltered points band in the Kaag lake.

Other

Grontmij made a nice overview of possible use cases.

Issues

The WCS of PDOK.nl does not seem to support v1.1.0, only 1.0.0 and 1.1.1.
The WMTS layer does not seem to work when zoomed out in QGIS.
The elements in the georss feed all have the same polygon (50.6 3.1 50.6 7.3 53.7 7.3 53.7 3.1 50.6 3.1). There is a kaartblad_index layer in the WFS. This can be used to find the correct coverage of each las file.

Structured info

The following text follows the schema.org convention and is used for structured search engines. See html source for details.

The Actueel Hoogtebestand Nederland versie 2 (AHN2), was made available . The dataset covers the topography of the Netherlands (nl), measured from 2011 through 2012.
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